1 files changed, 36 insertions, 21 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index b059a77b6081..c70c026c9a93 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
@@ -322,12 +322,13 @@ svm_migrate_copy_to_vram(struct amdgpu_device *adev, struct svm_range *prange,
 	for (i = j = 0; i < npages; i++) {
 		struct page *spage;
 
+		dst[i] = cursor.start + (j << PAGE_SHIFT);
+		migrate->dst[i] = svm_migrate_addr_to_pfn(adev, dst[i]);
+		svm_migrate_get_vram_page(prange, migrate->dst[i]);
+		migrate->dst[i] = migrate_pfn(migrate->dst[i]);
+
 		spage = migrate_pfn_to_page(migrate->src[i]);
 		if (spage && !is_zone_device_page(spage)) {
-			dst[i] = cursor.start + (j << PAGE_SHIFT);
-			migrate->dst[i] = svm_migrate_addr_to_pfn(adev, dst[i]);
-			svm_migrate_get_vram_page(prange, migrate->dst[i]);
-			migrate->dst[i] = migrate_pfn(migrate->dst[i]);
 			src[i] = dma_map_page(dev, spage, 0, PAGE_SIZE,
 					      DMA_TO_DEVICE);
 			r = dma_mapping_error(dev, src[i]);
@@ -522,9 +523,6 @@ svm_migrate_ram_to_vram(struct svm_range *prange, uint32_t best_loc,
 	pr_debug("svms 0x%p [0x%lx 0x%lx] to gpu 0x%x\n", prange->svms,
 		 prange->start, prange->last, best_loc);
 
-	/* FIXME: workaround for page locking bug with invalid pages */
-	svm_range_prefault(prange, mm, SVM_ADEV_PGMAP_OWNER(adev));
-
 	start = prange->start << PAGE_SHIFT;
 	end = (prange->last + 1) << PAGE_SHIFT;
 
@@ -886,7 +884,7 @@ svm_migrate_to_vram(struct svm_range *prange, uint32_t best_loc,
 static vm_fault_t svm_migrate_to_ram(struct vm_fault *vmf)
 {
 	unsigned long addr = vmf->address;
-	struct vm_area_struct *vma;
+	struct svm_range_bo *svm_bo;
 	enum svm_work_list_ops op;
 	struct svm_range *parent;
 	struct svm_range *prange;
@@ -894,29 +892,42 @@ static vm_fault_t svm_migrate_to_ram(struct vm_fault *vmf)
 	struct mm_struct *mm;
 	int r = 0;
 
-	vma = vmf->vma;
-	mm = vma->vm_mm;
+	svm_bo = vmf->page->zone_device_data;
+	if (!svm_bo) {
+		pr_debug("failed get device page at addr 0x%lx\n", addr);
+		return VM_FAULT_SIGBUS;
+	}
+	if (!mmget_not_zero(svm_bo->eviction_fence->mm)) {
+		pr_debug("addr 0x%lx of process mm is destroyed\n", addr);
+		return VM_FAULT_SIGBUS;
+	}
+
+	mm = svm_bo->eviction_fence->mm;
+	if (mm != vmf->vma->vm_mm)
+		pr_debug("addr 0x%lx is COW mapping in child process\n", addr);
 
-	p = kfd_lookup_process_by_mm(vma->vm_mm);
+	p = kfd_lookup_process_by_mm(mm);
 	if (!p) {
 		pr_debug("failed find process at fault address 0x%lx\n", addr);
-		return VM_FAULT_SIGBUS;
+		r = VM_FAULT_SIGBUS;
+		goto out_mmput;
 	}
 	if (READ_ONCE(p->svms.faulting_task) == current) {
 		pr_debug("skipping ram migration\n");
-		kfd_unref_process(p);
-		return 0;
+		r = 0;
+		goto out_unref_process;
 	}
-	addr >>= PAGE_SHIFT;
+
 	pr_debug("CPU page fault svms 0x%p address 0x%lx\n", &p->svms, addr);
+	addr >>= PAGE_SHIFT;
 
 	mutex_lock(&p->svms.lock);
 
 	prange = svm_range_from_addr(&p->svms, addr, &parent);
 	if (!prange) {
-		pr_debug("cannot find svm range at 0x%lx\n", addr);
+		pr_debug("failed get range svms 0x%p addr 0x%lx\n", &p->svms, addr);
 		r = -EFAULT;
-		goto out;
+		goto out_unlock_svms;
 	}
 
 	mutex_lock(&parent->migrate_mutex);
@@ -938,10 +949,11 @@ static vm_fault_t svm_migrate_to_ram(struct vm_fault *vmf)
 		goto out_unlock_prange;
 	}
 
-	r = svm_migrate_vram_to_ram(prange, mm, KFD_MIGRATE_TRIGGER_PAGEFAULT_CPU);
+	r = svm_migrate_vram_to_ram(prange, vmf->vma->vm_mm,
+				    KFD_MIGRATE_TRIGGER_PAGEFAULT_CPU);
 	if (r)
-		pr_debug("failed %d migrate 0x%p [0x%lx 0x%lx] to ram\n", r,
-			 prange, prange->start, prange->last);
+		pr_debug("failed %d migrate svms 0x%p range 0x%p [0x%lx 0x%lx]\n",
+			 r, prange->svms, prange, prange->start, prange->last);
 
 	/* xnack on, update mapping on GPUs with ACCESS_IN_PLACE */
 	if (p->xnack_enabled && parent == prange)
@@ -955,9 +967,12 @@ out_unlock_prange:
 	if (prange != parent)
 		mutex_unlock(&prange->migrate_mutex);
 	mutex_unlock(&parent->migrate_mutex);
-out:
+out_unlock_svms:
 	mutex_unlock(&p->svms.lock);
+out_unref_process:
 	kfd_unref_process(p);
+out_mmput:
+	mmput(mm);
 
 	pr_debug("CPU fault svms 0x%p address 0x%lx done\n", &p->svms, addr);